Study on the antimicrobial effect of silver-containing inner liners in refrigerators

Aims: To investigate the effect of silver-based antimicrobial material incorporated in the inner liners of refrigerators on food safety and quality. Methods and Results: In the first stage, the bactericidal effect was tested in the laboratory. Silver-containing samples and control plates were inoculated with different bacterial suspensions and stored at various temperatures. After defined storage periods the bacterial reduction was calculated by comparing viable cell count on reference plates and on silver-containing plates. The reduction caused by the silver-containing material varied between 1.0 and 5.9 log(10) units, depending on bacterial strain, incubation time and temperature. In the second stage, food storage experiments have been carried out. Thus, perishable foods were stored in coated and untreated refrigerators. After certain time periods the products were analysed for their sensorial and microbiological characteristics. A clear drop in viable counts both on the refrigerator wall and on the food was demonstrated using the silver-based antimicrobial material. Conclusions: Silver prevents refrigerators from being a hot spot for contaminants that could be transferred upon contact with food. Significance and Impact of the Study: This study provides original results regarding the antimicrobial activity of silver-containing refrigerator surfaces.